We are on a monthly rate that gives us more minutes than we use, so we don’t worry about the cost of using it.
Voice calls over Iridium are eye-wateringly expensive. Check out the calling rate to or from your terrestrial network 
I recall GBP 6.00 per minute – a few years ago. And the quality was extremely borderline – like the worst ever ATC audio quality.
For sure modern smartphones are rubbish compared to a Nokia 9310i. But even the last Nokia smartphones (e.g. the 808) outperformed anything out today on signal acquisition. The problem is that these old phones cannot run apps like Telegram which can get you wx data (using e.g. the Autorouter bot). So I don’t really think this helps when flying. GSM voice calls work poorly in flight because the signal is continually broken – unless you fly at the “UK burger run level” i.e. 1500ft and even then it probably won’t work for long.
Or you can call on your old Nokia GSM phone. The best phone is something that works on 900Mhz with a proper antenna and Bluetooth.
BTW my old Ericsson GH388 (which had a proper antenna) used to work well on my ski boat 15 Nm off shore at sea level. Now my fancy dual SIM smartphone drops calls in my house and I can see the phone mast out of the window! Modern technology hey – I have a phone which does all sorts of stuff except making phone calls.
huv wrote:
what is the TEL feature for?
Telephony. Calling home. Like ET. On Iridium.
I am lazy here, I know … but what is the TEL feature for?
I have about 30 hours on this. We installed because we needed the TEL feature, not specifically for the 3D, but I agree that it’s very nice, mainly for the ATIS split.
It goes without saying, of course, that you need stereo headsets as well.
I am not sure that I would invest in a new audio panel just for the feature, but if you have an excuse to change panel, it’s certainly worth going for.
You do need to configure it, though. A long press on something, I forget what. If you don’t, you will be initiatally disappointed.
Also, if you are only listening to one source, it goes back to the middle.
I said I would give some feedback when I’d tried it.
Like the post above, I am very impressed, it is great when listening to the ATIS on COM 2 whilst monitoring COM 1 which is often the same time you are just about to get handed over to another frequency to request entry to Class D Airspace.
Previously I had to mute COM 1 and worry about missing a call from ATC. Now I can clearly hear the ATIS in one ear – it is like listening into a conversation. …..very good.
Tried it for the first time last month. First having considered it a gimmick, it is actually much more useful than I imagined. And no, it is not just feeding different radios to different ears, it is digitally creating a precise sense of which direction the sound is coming from. So COM 1, COM 2 and intercom are coming from different directions. I am told that talk from back seat pax will actually sound as coming from behind. A very real advantage is the ability to read the ATIS on COM2 coming from the right while stille monitoring the busy TWR frequency sounding from the left. On one flight my “copilot” next to me could do that easily while I had a mono headset and was completely unable to distinguish the two and so could not read the ATIS.
I’ve had this for a few hundred hours now. It’s good enough that when picking up ATIS on box 2 I can listen to and understand ATC on box 1 without any problem. That’s with Zulus or A20s.
On music: I fly with music, and it’s very nice to share a playlist with the kids (or listen to theirs).
Yes I have just had a GMA345 installed but have only done one flight (which was picking it up from the Avionics shop) and now I am away on business.
I only had time to play with the Bluetooth phone function which is great. I’ll report on the 3D audio in 10 days when I’m back.
